| 摘要 |
745,220. Door-operating appliances. NAAMLOOZE VENNOOTSCHAP BRONSWERK. March 19, 1953 [April 4, 1952], No. 7617/53. Class 65 (1). A fluid-operated closure member 18 is pivoted about a fixed axis 3, and an element 4 of variable length is fixedly secured to the closure member with its longitudinal axis substantially at rightangles to the axis 3, the free end of said element being hingedly connected at 2 to one end of an arm of fixed length, the other end of which is pivoted about a fixed axis 1, and the arrangement being such that a straight line drawn between the axes 1 and 2 does not intersect the axis 3. As shown, the closure member is a fireproof door, the axes 1 and 3 are provided in a bracket 7 fixed to a wall 8, and the element 4 is a fluid-operated motor, the cylinder 10 of which is fixed to the door, the respective ends of the cylinder being supplied with pressure fluid via pipes 15, 16 through a control valve 19, and the piston-rod 13 being pivoted at 2 to the fixed arm. A reduced extension 9 of cylinder 10 accommodates an extension 11 of the main piston 12, cylinder 9 being provided with a spring-biased air outlet valve 17 and a similar air inlet valve (not shown), whereby cylinder 9 and piston 11 coact to function as checking means. The control valve is so arranged that it normally supplies fluid for moving the door towards the closed position. A spring 45 is compressed when the door is fully open to provide a starting impulse to the door when the latter is unlatched at the open position. The door may be arranged to rotate through 180 degrees, and the hinged edge of the door is then arranged to abut a spring-biased door post 44 when the door is in its closed position at 90 degrees from its open positions. |
